发明名称 |
Method and apparatus for bus access allocation |
摘要 |
A method for granting access to a bus is disclosed where a fair arbitration is modified to account for varying conditions. Each bus master (BM) is assigned a Grant Balance Factor value (hereafter GBF) that corresponds to a desired bandwidth from the bus. Arbitration gives priority BMs with a GBF greater than zero in a stratified protocol where requesting BMs with the same highest priority are granted access first. The GBF of a BM is decremented each time an access is granted. Requesting BMs with a GBF equal to zero are fairly arbitrated when there are no requesting BMs with GBFs greater than zero wherein they receive equal access using a frozen arbiter status. The bus access time may be partitioned into bus intervals (BIs) each comprising N clock cycles. BIs and GBFs may be modified to guarantee balanced access over multiple BIs in response to error conditions or interrupts.
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申请公布号 |
US7065595(B2) |
申请公布日期 |
2006.06.20 |
申请号 |
US20030249271 |
申请日期 |
2003.03.27 |
申请人 |
INTERNATIONAL BUSINESS MACHINES CORPORATION |
发明人 |
DRERUP BERNARD C.;GANASAN JAYA P.;HOFMANN RICHARD G. |
分类号 |
G06F13/362;G06F13/36 |
主分类号 |
G06F13/362 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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